The present invention relates to a supporting apparatus and a vibration generator utilizing the same, suitably used for supporting a moving portion which reciprocates in predetermined vibrating directions, such as a vibrating table in a vibration generator.
In a vibration generator, it is important to prevent a so-called cross vibration, and to reciprocate a vibrating table, which serves as a moving portion, along a predetermined single axis (vibrating directions). The term cross vibration means that the vibrating table moves crosswise, in directions vertical to the predetermined directions (hereinafter, the crosswise directions ray also be called radial directions). In order to prevent the cross vibration, the vibration generator uses a supporting apparatus provided between the vibrating table and a fixed portion provided by such equipment as an exciting machine disposed around the vibrating table. The supporting apparatus guides the vibrating table in the vibrating directions, and limits the movement of the vibrating table in the radial directions.
FIG. 11 shows a constitution of a prior art supporting apparatus 41, with diagram (a) being a plan view showing with partial cutout, and diagram (b) being a side view. The supporting apparatus 41 is constituted by sandwiching a rocker 44 between a fixed-side receiver plate 42 attached to the fixed portion and a moving-side receiver plate 43 attached to the vibrating table serving as a moving portion, and by connecting the rocker 44 with the fixed-side receiver plate 42 and the moving-side receiver plate 43 with four connecting members 45. The rocker 44 is rigid in the radial directions, and has arcuate surfaces respectively facing the receiver plates 42, 43. Each of the arcuate surfaces represents a part of the outer circumferential surface of a column assumed on a diameter as being the distance between the receiver plates 42, 43. Each of the connecting members 45 is formed of an elastic member such as rubber, or a synthetic resin such as nylon, polypropylene and so on, and is pressed between a sandwiching plate 46 provided on the receiver plates 42, 43 and another sandwiching plate 47 provided on the rocker 44. With the arrangement described above, the fixed-side receiver plate 42 is attached to a fixed block 48 fastened to the fixed portion.
According to the supporting apparatus 41, the vibrating table can move in vibrating directions because the connecting members 45 undergo deformation, Due to the movement of the vibrating table, the rocker 44 also moves accompanying the deformation of the connecting members 45, while the arcuate surfaces of the rocker 44 keep contact with the respective receiver plates 42, 43. With this constitution, the movement of the vibrating table in the radial directions is limited by the rocker 44.
According to the supporting apparatus 41 described above, since the fixed portion and the vibrating table are interconnected by the connecting members 45, there Is a problem that the connecting portions are subjected to repeated stress, which makes the connecting portions susceptible to fatigue fracture, and makes difficult to improve durability.
Further, a moving range of the vibrating table is limited within a range of deformation of the connecting members 41. Thus, in order to increase the moving range of the vibrating table, the size of the supporting apparatus 45 must be increased, which leads to a problem of increased cost.
Further, if the size of the supporting apparatus 41 is increased, a mass of the moving portion increases, which decreases acceleration to the vibrating table, and makes impossible to generate a vibration having a desired vibration waveform, resulting in decreased reliability of the vibration generator.
The present invention is made in order to solve the above described shortcomings in the prior art, and it is therefore an object of the present invention to provide a supporting apparatus which can be manufactured at a reduced cost while having an increased durability. Another object of the present invention is to provide a supporting apparatus capable of generating a vibration having a desired vibration waveform, thereby increasing the reliability.
A supporting apparatus according to claim 1 is a supporting apparatus disposed between a fixed portion and a moving portion facing the fixed portion at a predetermined distance, for supporting the moving portion which vibrates while maintaining parallelism to the fixed portion, and is characterized In that the moving portion and the fixed portion are respectively provided with receiving members 2F, ZM facing each other; and the receiving members 2F, 2M sandwich, under pressure, a rocking member 4 which limits a movement of the moving portion in crosswise directions Y vertical to vibrating directions R of the moving portion, while rocking about its axis accompanying the vibration of the moving portion in the vibrating directions R.
According to the supporting apparatus provided by claim 1, when the moving portion moves In the predetermined vibrating directions R, the moving-side receiving member 2M also moves, and the rocking member held under pressure between the receiving members 2F, 2M rocks about its axis, making possible to follow the movement of the moving portion. In this case, the rocking member 4 limits the movement of the moving portion in the crosswise directions Y vertical to the vibrating directions R. In other words, the moving portion moves (vibrates) with respect to the fixed portion only in the rocking directions R, and the crosswise movement is prevented. In addition, since the rocking member 4 can be assembled by sandwiching the rocking member between the pair of receiving members 2F, 2M, assembling operation as of the entire apparatus becomes easy. Further, even if the rocking member 4 must be replaced, the replacement can be performed easily.
According to the supporting apparatus provided by claim 1, the cross vibration can be prevented, and the apparatus can be used stably as a supporting apparatus of this kind. Further, since the rocking member should only be sandwiched between a pair of the receiving members, assembling operation of the supporting apparatus becomes easy, and replacement of the rocking member also becomes easy.
A supporting apparatus according to claim 2 is characterized in that the pair of receiving members 2F, 2M each has a flat surface 3 parallel to the vibrating directions R of the moving portion; the rocking member 4 includes a roller portion 4a and an engaging portion 4b; the roller portion 4a has an axis of rotation along the crosswise directions Y; the roller portion 4a has an outer circumferential surface making linear contact with each flat surface 3 of the receiving members 2F, 2M In the crosswise directions Y upon installation of the rocking member 4; and the rocking member 4 is held between the pair of receiving members 2F, 2M by engagement between the engaging portion 4b and the pair of receiving members 2F, 2M during a travel, by rolling, of the roller portion 4a accompanying a reciprocating movement of the moving portion.
According to the supporting apparatus provided by claim 2, the roller portion 4a travels by rolling. It should be noted here that hereinafter, traveling by rolling will be called xe2x80x9crollingxe2x80x9d. Now, the rolling of the roller portion 4a causes the entire rocking member 4 to travel (rock), However, the engagement between the engaging portion 4b of the rocking portion 4 with the pair of receiving members 2F, 2M keeps the rocking member 4 between the pair of receiving members 2F, 2M. Further, the rolling of the roller portion 4a guides the moving portion in the vibrating directions R, and the outer circumferential surface of the roller portion 4a makes the linear contact with each flat surface 3 of the pair of receiving members 2F, 2M along the crosswise directions Y. Therefore, there is a large friction in the crosswise directions Y, reliably limiting the movement of the moving portion in the crosswise directions Y vertical to the vibrating directions R. Further, the rocking member 4 is held by the receiving members 2F, 2M, and the vibration of the moving portion is stabilized.
According to the supporting apparatus provided by claim 2, since the movement of the moving portion in the crosswise directions (radial directions) vertical to the vibrating directions is limited by the roller portion, the rocking member can have a relatively simple shape. This makes easy to manufacture the rocking member including the roller portion, and makes possible to reduce the cost of manufacture. Further, the movement of the moving portion in the crosswise directions vertical to the vibrating directions is reliably limited, resulting in a superb performance as a supporting apparatus of this kind. Further, since the roller portion does not move in the crosswise directions, the roller portion is less susceptible to wear and chipping, making possible to improve durability.
A supporting apparatus according to claim 3 is characterized in that the engaging portion 4b includes a pair of first and second engaging members 8a, 8b each having arcuate engaging surfaces C, C respectively on a side facing the fixed portion and on a side facing the moving portion, in symmetry with respect to the axis of rotation; the first and the second engaging portions 8a, 8b are disposed side by side, on the axis of rotation, in a mutually inverted relationship; each of the receiving members 2F, 2M is provided with a pair of slanted surfaces slanting at a same angle but in opposite directions; the mutually-facing slanted surfaces 16, 17 are slanted in a same direction; each of the first and the second engaging members 8a, 8b is disposed between the receiving members 2F, 2M, with respective engaging surfaces (C) . . . contacting a corresponding one of the slanted surfaces 16, 17; and the engaging surfaces of the engaging portion 4b and the slanted surfaces of the receiving members 2 keep contact during the travel, by rolling, of the roller portion 4a accompanying the reciprocating movement of the moving portion.
According to the supporting apparatus provided by claim 3, the first and the second engaging members 8a, 8b are disposed between the receiving members 2F, 2M, the engaging surfaces of the first and the second engaging members 8a, 8b are disposed on the fixed side and on the moving side respectively, In symmetry with respect to the axis of rotation, and the first and the second engaging members 8a, 8b are disposed in a mutually inverted relationship. Therefore, disengaging directions for the first and the second engaging members 8a, 8b to come out of the pair of receiving members 2F, 2M are different from each other. With this arrangement, even if the moving portion travels (vibrates) with respect to the fixed portion, the rocking member 4 sandwiched between the pair of receiving members 2F, 2M does not fall off from between the receiving members 2F, 2M.
According to the supporting apparatus provided by claim 3, the rocking member does not fall off even when traveling in the vibrating directions, and is held between the pair of receiving members. Therefore, a stable supporting apparatus is provided.
A supporting apparatus according to claim 4 is characterized in that the rocking member 4 is constituted by connecting the roller portion 4a and the engaging portion 4b each formed individually, and that the first and the second engaging members 8a, 8b of the engaging portion 4b are members having a same shape,
According to the supporting apparatus provided by claim 4, the rocking member 4 is constituted by assembling the roller portion 4a and the engaging portion 4b each formed:individually. Therefore, as compared to the case in which the rocking member 4 is formed integrally, a shape of the parts to be manufactured is simpler, which makes possible to easily manufacture the roller portion 4a and the engaging portion 4b. Further, the engaging portion 4b is constituted by assembling a pair of engaging members 8a, 8a having a same shape. Therefore, as compared to the case in which the engaging portion 4b is formed integrally, a shape of the parts to be manufactured is simpler, and it Is necessary to manufacture only one kind of the engaging member 8. Further, since the engaging member 8 is only one kind, storage and handling of the engaging portion 5 become easy, and an assembling operation becomes simple.
According to the supporting apparatus provided by claim 4, the rocking member is constituted as an assembly of the individually formed roller portion and the engaging portion. Therefore, as compared to the case in which the rocking member is formed integrally, a shape of the parts to be manufactured is simpler. This makes possible to manufacture the roller portion and the engaging portion easily, and to reduce the cost of manufacture. Further, the engaging portion is constituted as an assembly of a pair of engaging members having a same shape. Therefore, as compared to the case in which the engaging portion is formed integrally, a shape of the parts to be manufactured is simpler, and it is necessary to manufacture only one kind of the engaging member, making possible to further reduce the cost of manufacture. Further, since the engaging member is only one kind, storage and handling of the engaging portion become easy, and assembling operation becomes simple.
A supporting apparatus according to claim 5 is characterized in that the fixed-side receiving member 2F and the moving-side receiving member 2M have a same shape, and are disposed in symmetry with respect to the axis of rotation of the rocking member 4.
According to the supporting apparatus provided by claim 5, the pair of receiving members 2F, 2M attached to the fixed portion and the moving portion respectively have an identical shape. Therefore, it is necessary to manufacture only one kind of the receiving member 2. Further, since the receiving member 2 is only one kind, storage and handling of the receiving member 2 become easy, and assembling operation becomes simple.
According to the supporting apparatus provided by claim 5, it is necessary to manufacture only one kind of the receiving member 2, and it is possible to reduce the cost of manufacture. Further, since the receiving member is only one kind, storage and handling of the receiving member 2 become easy, and assembling operation becomes easy.
A supporting apparatus according to claim 6 is characterized in that at least one of the fixed-side receiving member 2F and the moving-side receiving member 2M is provided with a limiting member 6 for limiting an axial movement of the rocking member 4.
According to the supporting apparatus provided by claim 6, the limiting member 6 limits the movement of the rocking member 4 in the axial directions (crosswise directions Y). Therefore, the rocking member 4 can be reliably held between the pair of receiving members 2F, 2M, and thus it is possible to stably support the moving portion.
According to the supporting apparatus provided by claim 6, the rocking member can be reliably held between the pair of receiving members, and the moving portion can be stably supported.
A vibration generator according to claim 7 comprises a vibrating table 32 and a main body 34 including an exiting machine 33 for giving the vibrating table 32 a vibration in directions along a predetermined single axis R. The generator is characterized in that the vibrating table 32 provides a moving portion, the main body 34 providing a fixed portion, a plurality of supporting apparatuses 1 according to one of claims 1-6 being disposed between the main body 34 and the vibrating table 32 for supporting the vibrating table 32.
According to the vibration generator provided by claim 7, the supporting apparatuses 1 prevent movement in the crosswise directions Y vertical to the vibrating directions R, thereby making possible to stably support the vibrating table 32. Therefore, it becomes possible to generate a vibration having a predetermined vibration waveform, and improve reliability as the vibration generator.
According to the vibration generator provided by claim 7, since the vibrating table can be stably supported by the supporting apparatuses, it becomes possible to generate a vibration having a predetermined vibration waveform, and improve reliability as the vibration generator.